Having operated from the W1KM station, that has 40, 80, and 160M 4-squares
in a salt water marsh,
your success may depend on how much salt water intrusion you have into the
marsh each day. That's
something that pictures may not tell, but a quick taste of the water at
high tide will tell you if its salty
or fresh. The saltier the better for the low bands- it will reduce losses
in the near field of the antenna
as you improve the ground conductivity.
The salt water intrusion into the marsh at W1KM is high enough that, when
there is storm surge, the bottoms
of the verticals are shorted out by the seawater. That's also produced
problems when there is ice in the water-
more than once it has broken the insulating pipes that the verticals sit on.
Dennis W1UE
On Sat, Apr 20, 2019 at 10:10 AM Ray Higgins (W2RE) <ray.w2re@gmail.com>
wrote:
> Thanks for the valuable information.
>
> I did receive some personally notes not shared here on Topband, thanks for
> the help and the kind words. One indvidual specifically asked If I would
> share my experience in some sort of presentation about building remote
> stations, he was interested in the logistics from finding land to local
> zoning and the actual build. I never thought about doing a presentation but
> it was an intriguing inquiry, I did send him an album in chronological
> order of pictures and video (drone) two of the many remote stations we have
> built the past few years. Both albums have the start to finish…actually we
> are never really finished!. With that said, here is the two albums if
> others are interested.
>
> W1/Eastport https://goo.gl/photos/hEX1A4UR6wC6Lopp7 <
> https://goo.gl/photos/hEX1A4UR6wC6Lopp7> 63/ac
>
> W1/Lubec https://photos.app.goo.gl/oFEmGbpA3eWo8D143 <
> https://photos.app.goo.gl/oFEmGbpA3eWo8D143> 20/ac
>
> So, building a remote station 500 miles away from my home-base is nothing
> new to me! While I’m uncertain if my new personal QTH with nearby marsh
> will have any effect on the low band antennas, I pretty optimistic the
> station will play regardless. :)
>
> Thanks again,
>
> Ray Higgins
> W2RE.com
>
>
>
>
>
>
>
>
>
>
>
> > On Apr 20, 2019, at 4:16 AM, shristov <shristov@ptt.rs> wrote:
> >
> >> donovanf@starpower.net wrote:
> >
> >> The classic source for Fresnel zones as they apply to HF site
> >> selection is NBS Technical Note 139:
> >> https://nvlpubs.nist.gov/nistpubs/Legacy/TN/nbstechnicalnote139.pdf
> >
> >
> > This indeed is a classical source, but it should be noted that the
> derivation
> > assumes that the elevation angle actually used for communication
> > is equal to the elevation angle of the peak of lowest ground reflection
> lobe.
> >
> > This may or may not be the case.
> >
> > In amateur operation, communication is often done using elevation angles
> > well below the peak of the lowest lobe, because of inability to erect
> very high antennas.
> > In such cases, the first Fresnel zones extends much further than the
> > equation 3.4-4 predicts. Correct formulas may be derived using the same
> > procedure, while separating communication angle from lobe peak angle.
> >
> > Using vertical antennas additionally complicates matters.
> > I am not aware of any work on this topic.
> >
> >
> > 73,
> >
> > Sinisa YT1NT, VE3EA
> >
> >
> >
> > _________________
> > Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
> _________________
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> Reflector
>
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